Rotation input device for a capacitive sense cord

ABSTRACT

This document describes techniques and devices for a rotation input device for a capacitive sense cord. A cord may be constructed that includes a cable, a plurality of sensing wires, and a rotation input device. The sensing wires are twisted around one another within a cable jacket of the cable throughout an insensitive portion of the cord that is insensitive to touch input. The rotation input device includes the plurality of sensing wires disposed proximate to a surface of the cord and positioned lengthwise along the cord to provide a capacitively sensitive portion of the cord. The plurality of sensing wires are independently sensitive to touch input. Also, the rotation input device is configured to enable rotational input based on a pattern of change in capacitance values corresponding to at least a subset of the plurality of sensing wires in the rotation input device.

RELATED APPLICATION

This application is a continuation of and claims the benefit of U.S.Utility application Ser. No. 16/010,173 filed Jun. 15, 2018 which inturn claims priority under 35 U.S.C. § 119(e) to U.S. Provisional PatentApplication Ser. No. 62/562,659 filed Sep. 25, 2017, the disclosures ofwhich are hereby incorporated by reference in their entireties herein.

BACKGROUND

In-line controls for cords are standard and ubiquitous for devices suchas earbuds or headphones for music players, cellular phone usage, and soforth. Similar in-line controls are also used by cords for householdappliances and lighting, such as clocks, lamps, radios, and fans.Generally, such in-line controls are implemented via a combox that isin-line in the cord. The combox generally includes, among other parts, aprinted circuit board (PCB), one or more buttons, an enclosure, andstrain relief. However, implementing the combox imposes rigid designconstraints on the product and increases the cost of the product.Conventional comboxes also have problems with intrusion due to moisture(e.g., sweat) and skin, which can lead to corrosion of internal controlsand electrical shorts.

SUMMARY

This document describes techniques and devices for a rotation inputdevice for a capacitive sense cord. A capacitive sense cord includes acable, a rotation input device, and a cover that covers the cable andthe rotation input device. The capacitive sense cord may be implementedas a variety of different types of cords, such as a cord for headphones,earbuds, data transfer, lamps, clocks, radios, fans, and so forth. Thecover can be formed from a flexible, waterproof material that seals thecable and prevents water from permeating the seal. In implementations,the cover is configured to enable reception of touch input that causes achange in one or more capacitance values associated with sensing wiresof the rotation input device. A controller, implemented at the cord or acomputing device coupled to the cord, can detect the change in thecapacitance values and trigger one or more functions associated with thechange in capacitance values. For example, when implemented as a cordfor a headset (e.g., headphones or ear buds), the controller can controlaudio to the headset, such as by playing the audio, pausing the audio,adjusting the volume of the audio, skipping ahead in the audio, skippingbackwards in the audio, skipping to additional audio, and so forth.

This summary is provided to introduce simplified concepts concerning arotation input device for a capacitive sense cord, which is furtherdescribed below in the Detailed Description. This summary is notintended to identify essential features of the claimed subject matter,nor is it intended for use in determining the scope of the claimedsubject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of techniques and devices for a rotation input device for acapacitive sense cord are described with reference to the followingdrawings. The same numbers are used throughout the drawings to referencelike features and components:

FIG. 1 is an illustration of an example environment in which techniquesusing, and objects including, a rotation input device for a capacitivesense cord may be implemented.

FIG. 2 illustrates additional environments in which a capacitive sensecord may be implemented.

FIG. 3 illustrates an example system configured to detect input to arotation input device of a capacitive sense cord.

FIG. 4 illustrates an example of providing rotational input to arotation input device of a capacitive sense cord.

FIG. 5 illustrates an example structure of a rotational input device ona capacitive sense cord.

FIG. 6 illustrates example diagrams of rotational input provided to arotation input device of a cord.

FIG. 7 illustrates a method of detecting rotational input with acapacitive sense cord.

FIG. 8 illustrates various components of an example computing systemthat can be implemented as any type of client, server, and/or computingdevice as described with reference to the previous FIGS. 1-7 toimplement a rotation input device for a capacitive sense cord.

DETAILED DESCRIPTION

Overview

This document describes techniques and devices for a rotation inputdevice for a capacitive sense cord. The cord may be implemented as avariety of different types of cords, such as a cord for headphones,earbuds, data transfer, lamps, clocks, radios, fans, and so forth. Inanother example, the cord may be implemented as a touchcord that cansense touch input at one or more locations along the cord.

The cord can be constructed of a cable, multiple capacitive sensingwires, an optional shield wire, and a cover. Any of the sensing wires orshield wire can be implemented as solid or stranded wires. Inimplementations, the wires are twisted around themselves inside thecable throughout a portion of the cord, such that the cord isinsensitive to touch input throughout that portion of the cord. Forexample, the sensing wires can be a separate bundle inside an existingheadphone cable. At least one portion of the cord is implemented as acapacitively sensitive interface (described herein as a “rotation inputdevice”) that is sensitive to touch input. In the capacitively sensitiveinterface, the sensing wires are disposed near a surface of the cord,but still under the cover, and run lengthwise along the cable. After thecapacitively sensitive interface, the sensing wires are again twistedtogether, or can optionally be terminated and not continue past thecapacitively sensitive area. In addition, the cover can be configured tocompletely cover the wires and cable, secure them in place, and hidethem from a user and the environment.

Using the sensing wires, a controller can detect a pattern of changingcapacitance values of different sensing wires when a user rotates therotation input device between the user's thumb and finger. For example,as the rotation input device is rolled between two of the user'sfingers, the touch input provided by the user's fingers on opposingsides of the rotation input device moves around the surface of therotation input device and causes a temporary change in capacitance todifferent individual sensing wires, which creates a pattern ofcapacitance changes from one sensing wire to the next. This pattern isused to detect rotational input to the rotation input device.

It is also possible for the sensing wires to be used to sense inputsother than rotation of the rotation input device between the thumb andfinger. For example, taps can be detected based on short impulses in thecapacitive response of the sensing wires. In another example, a “grab”gesture can be detected based on a large, sustained rise in thecapacitive response. The electrodes can also be patterned on therotation input device, such that each unique gesture activates aparticular subset of electrodes, in a particular way, which iscomputationally distinguishable from other kinds of gestures a usermight perform.

A rotation input device on a cord that can detect various types of touchinput eliminates the need for moving parts, hardware, bulk, andthickness found in existing in-line controls for cords. At the sametime, the cost to manufacture the in-line controls is reduced becausethere are no extra hardware controls that must be electricallyconnected. Additionally, manufacturing challenges resulting from fibersbeing woven into a long structure are reduced. Furthermore, thecontroller can be implemented to detect different types of touches tothe sensing wires (e.g., rotation, long presses versus quick taps,pinches, or a sequence of touches) thereby increasing the total numberof different functions that can be triggered from the cord.

The controller measures one or more capacitance values associated withthe sensing wires. In response to detecting a pattern of change in theone or more capacitance values, the controller determines that thepattern of change in the capacitance values corresponds to rotationalinput caused by the user twisting or rotating the rotation input deviceof the cord. In some cases, the controller can also determine thedirection of the rotational input (e.g., clockwise or counterclockwisearound a longitudinal axis of the rotation input device). Then, thecontroller initiates one or more functions based on the rotationalinput, such as increasing or decreasing the volume, scrolling throughmenu items, and so forth. In some cases, the cord can be furtherconfigured to detect tap or grab input caused by the user tapping orpressing and holding his or her fingers on the capacitively sensitiveinterface on the cord, and distinguish the rotational input from the tapor grab input.

Example Environment

FIG. 1 is an illustration of an example environment 100 in whichtechniques using, and objects including, a rotation input device for acapacitive sense cord may be implemented. Environment 100 includes acapacitive sense cord 102, which has a capacitively sensitive portion104 that is sensitive to touch input and an insensitive portion 106 thatis not sensitive to touch input. In the environment 100, the cord 102 isillustrated as a cord for a headset. While the cord 102 is described asa cord for a headset, such as earbuds or headphones, the cord 102 may beutilized for various other types of uses, such as cords for appliances(e.g., lamps or fans), USB cords, SATA cords, data transfer cords, powercords, or other types of cords that are used to transfer data or media.

Consider FIG. 2, which illustrates additional environments 200 in whichthe cord 102 can be implemented. In one example, the cord 102 isimplemented as a data transfer cord configured to transfer data (e.g.,media files) between a computer 202 and a mobile device 204. In thisexample, the cord 102 may be configured to receive touch input usable toinitiate or pause the transfer of data between computer 202 and mobiledevice 204.

As another example, at an environment 206, the cord 102 is illustratedas a power cord for a lamp 208. In this example, the cord 102 may beconfigured to receive touch input usable to turn on and off the lampand/or to adjust the brightness of the lamp.

Returning to FIG. 1, the cord 102 includes a cover 108 (e.g., cablejacket), which is configured to cover a cable 110 of the cord 102. Thecord 102 also includes a rotation input device 112. In FIG. 1, a cutawayview shows an example of the rotation input device 112, which includes aportion of the cover 108 and the cable 110 beneath the cover 108. Inthis example, the cable 110 is configured to communicate audio data to aheadset. In other implementations, however, the cable 110 can beimplemented to transfer power, data, and so forth.

Instead of using separate hardware controls, the cord 102 is configuredto capacitively sense touch input via the rotation input device 112. Todo so, the cord 102 includes sensing wires 114. The sensing wires 114are formed from conductive wire, which may be implemented using any of avariety of different conductive materials, such as copper, silver, gold,or aluminum. These sensing wires 114 are twisted within the cable 110throughout most of the cord 102, but are disposed proximate to an insidesurface of the cover 108 at the rotation input device 112, such that thesensing wires 114 are positioned near the surface of the cord 102. Inthis way, the rotation input device 112 is implemented as a capacitivesensing interface. The sensing wires 114 run lengthwise along therotation input device 112 of the cord 102, and each sensing wire 114 isscanned individually to determine a capacitance value and any changes tothe capacitance value. For example, when a finger of a user's handapproaches one or more sensing wires 114, the finger causes thecapacitance of those sensing wires 114 to change (e.g., increase ordecrease) based on the proximity of the finger to those sensing wires114.

In the environment 100, the cord 102 includes earbuds 116 and aconnector 118-1 that is configured to be plugged into, magneticallycoupled to (e.g., connector 118-2), or otherwise communicatively coupledto, the computing device 120. The computing device 120 is illustrated asa mobile phone, but may also be configured as a desktop computer, alaptop computer, a tablet device, a wearable device, and so forth. Thus,the computing device 120 may range from full resource devices withsubstantial memory and processor resources (e.g., personal computers,game consoles) to low-resource devices with limited memory and/orprocessing resources (e.g., mobile devices).

The computing device 120 is illustrated as including the controller 122,which is representative of functionality to sense touch input to therotation input device 112 of the cord 102, and to trigger variousfunctions based on the touch input. For example, when the cord 102 isimplemented as a cord for a headset, the controller 122 can beconfigured to, in response to touch input to the rotation input device112, start playback of audio to the headset, pause audio, skip to a newaudio file, adjust the volume of the audio, and so forth. In FIG. 1, thecontroller 122 is illustrated as being implemented at the computingdevice 120, however, in alternate implementations, the controller 122may be integrated within the cord 102, or implemented with anotherdevice, such as powered headphones, a lamp, a clock, and so forth.Having discussed an example environment 100 in which the cord 102 may beimplemented, consider now a more-detailed discussion of how thecontroller 122 detects touch input to the rotation input device 112 totrigger various functions.

Generally, the controller 122 is configured to scan the one or moresensing wires 114 of the rotation input device 112 to detect a change incapacitance to the sensing wires 114, which corresponds to touch inputto the rotation input device 112.

Consider FIG. 3, which illustrates an example system 300 configured todetect touch input to a capacitively sensitive interface on the cord102. In the system 300, touch input 302 is provided to a capacitivelysensitive interface of the cord 102, such as an area corresponding tothe rotation input device 112.

A variety of different types of touch input 302 may be provided. In oneor more implementations, the touch input 302 may correspond to a patternor series of touches to the rotation input device 112. As an example, auser may provide touch input by pinching the rotation input device 112.Doing so may trigger a function that is different than a functiontriggered by simply touching or tapping the rotation input device 112.In some aspects, after pinching the rotation input device 112, the usermay roll the rotation input device 112 between the user's fingers torotate the rotation input device 112 clockwise or counterclockwisearound a longitudinal axis of the rotation input device 112. As the userrotates the rotation input device 112, different sensing wires runninglengthwise along the rotation input device 112 experience changes incapacitance, such that a pattern of changes in capacitance is detected.Further detail of this and other aspects is described below.

By way of example, consider FIG. 4, which illustrates an example 400 ofproviding touch input to a capacitively sensitive interface of a cord.In the example 400, a user grips the rotation input device 112 of thecord 102 between a thumb 402 and a forefinger 404, such that the thumb402 and the forefinger 404 contact opposing sides of the rotation inputdevice 112. When the thumb 402 and forefinger 404 move close to therotation input device 112, the sensing wires 114 underneath the cover108 that are proximate the thumb 402 and forefinger 404 experience achange in capacitance. In some cases, the touch input can be provided bymoving the thumb 402 or the finger 404 close to the rotation inputdevice 112 without physically touching the rotation input device 112.

Returning to FIG. 3, at 304, the controller 122 detects a change incapacitance to at least some of the sensing wires 114, associated withthe rotation input device 112, when the touch input 302 is provided tothe rotation input device 112 of the cord 102. To sense the touch input302, the controller 122 may use a capacitance meter that can detect thechange in capacitance of a single sensing wire or multiple sensing wiresdisposed parallel to each other. Generally, when a finger touches, orcomes in close contact to, a sensing wire 114, a capacitance is formedbetween the finger and the associated sensing wire 114. This capacitancemay be detected by the capacitance meter of the controller 122 todetermine that the touch input has occurred.

The controller 122 may be implemented to detect the change incapacitance in a variety of different ways, such as usingself-capacitance sensing, which detects a change in capacitance of anelectrically charged sensing wire. In this case, the sensing wire 114 isnot grounded. When not being touched, a small baseline capacitanceexists, which may be measured by the capacitance meter. When the user'sfinger comes in the vicinity of the sensing wire 114, however, atouch-input capacitance is formed between the fingertip and the sensingwire 114. This capacitance is electrically connected in parallel to thebaseline capacitance, causing the capacitance meter to detect the touchinput.

At 306, in response to detecting the change in capacitance or a patternof capacitance changes, the controller 122 triggers a functionassociated with the touch input 302. Notably, the controller 122 cantrigger a variety of different types of functions based on how the cord102 is being utilized. For example, when the cord 102 corresponds to acord for a headset, the controller 122 may trigger functions such asplaying audio (e.g., a song, a video, an audiobook file, or a voicememo), pausing audio, fast forwarding audio, skipping to a next audiotrack, adjusting the volume of the audio, and so forth. As anotherexample, when the cord 102 corresponds to a data transfer cord, thecontroller 122 may trigger functions such as starting the transfer ofdata, stopping the transfer of data, authenticating the user to enablethe transfer of data, and so forth. When the cord 102 corresponds to acord for an appliance (e.g., a lamp, a fan, or an alarm clock), thecontroller 122 may trigger functions such as turning on or off theappliance, adjusting the brightness of a lamp, adjusting the speed of afan, activating the snooze button on an alarm clock, and so forth.

In some cases, functions may be associated with various combinations,sequences, or patterns of rotational touch input to the rotation inputdevice 112. For example, a function may be associated with a firstclockwise rotation of the rotation input device 112, while a differentfunction may be associated with a sequence of rotations, such as aclockwise rotation followed by a quick counterclockwise rotation andthen another clockwise rotation. Other rotational patterns are alsocontemplated, which may be mapped to any suitable function.

FIG. 5 illustrates an example implementation 500 of the rotation inputdevice 112 of the cord 102. As noted, the cord 102 is constructed withcapacitive sensing wires 114, the cable 110, and the cover 108.Optionally, the cord 102 can also include a shield wire, which isdiscussed in further detail below. The example implementation 500illustrates the cable 110 and six capacitive sensing wires 114underneath the cover 108. The sensing wires 114 are twisted aroundthemselves inside the cable 110 throughout a substantial length of thecord 102, such as above and below the rotation input device 112. Thecord 102 is insensitive to touch input where the sensing wires 114 aretwisted around themselves. In aspects, the sensing wires 114 are twistedaround themselves throughout the insensitive portion 106 of the cord102.

In the rotation input device 112, however, the sensing wires 114 arebrought near the surface of the cord 102, such as proximate to an insidesurface of the cover 108, and run straight along the length of thecable. Here, the sensing wires 114 are independently sensitive to touchinput. Further, within the rotation input device 112, the sensing wires114 run substantially parallel to one another and the cable 110. Thisconfiguration allows the rotation input device 112 to be capacitivelysensitive to touch input. In addition, the sensing wires 114 are spacedapart from one another by a mechanical object 502. The mechanical object502 can include any suitable object, examples of which include a plasticpart, or a portion of an inner core of the cord 102 that is locallythicker within the rotation input device 112. The cover 108 can beformed from any suitable material, examples of which include a siliconrubber or thermoplastic elastomer (TPE) overmold to completely cover thewires, secure the wires in place, and hide and protect them from theenvironment. The material used for the cover 108 is configured to be aflexible, waterproof material that seals the cable and prevents waterfrom permeating the seal. Although the example implementation 500 isillustrated with six sensing wires 114, any suitable number of sensingwires 114 can be used, such as 7, 8, 9, 10, or more wires. Three wirescan be used as a minimum number of sensing wires to detect rotationalinput.

Consider, for example, FIG. 6, which illustrates cutout examples 600 ofrotational input provided to the rotation input device 112 of the cord102. When the sensing wires 114 are disposed proximate to the surface ofthe cord 102, the sensing wires 114 are arranged in a manner suitable todetect rotation between the user's thumb and forefinger. At 602, a firstexample is illustrated in which a user touches the rotation input device112 on opposing sides (approximately 180 degrees apart in relation to acenter axis of the cord 102) of the rotation input device 112 using twofingers, such as the thumb 402 and the forefinger 404. Here, therotation input device 112 includes three sensing wires 114 correspondingto three capacitance-sensing channels, such as integrated circuit (IC)channels, e.g., channels “1”, “2”, and “3”. The sensing wires have aspatial orientation that enables detection of rotational input to therotation input device 112. For example, the sensing wires 114 areequally spaced around a center portion 604 of the rotation input device112.

At 602, a change in capacitance is detected via channel “1” based on theproximity of the user's forefinger 404 to a sensing wire 114corresponding to the channel “1”. At 606, the user's thumb 402 moves tothe left while the user's forefinger 404 moves to the right. Based onthis movement, the forefinger 404 moves away from channel “1”, whichreduces the amount of change in capacitance of the sensing wire onchannel “1”, causing a capacitance value of channel “1” to begin toreturn to its original or base value. In addition, the thumb 402 movestoward the sensing wire associated with channel “3”, which changes thecapacitance of that sensing wire. Continuing the movement of the thumb402 and forefinger 404 may then result in a capacitance change to asensing wire on channel “2” while the capacitance value of channel “3”begins to return to its original or base value. Accordingly, a sensingpattern of capacitance changes over a duration of time can be detectedas capacitance changes via channels “1”, “3”, and then “2”, whichindicates a counterclockwise rotation of the rotation input device 112,or movement of the user's fingers around the rotation input device 112in a clockwise direction. If the user rolls the rotation input device112 in the opposite direction, then the pattern of capacitance changesmay be detected over a duration of time via channels “1”, “2”, and then“3”, which indicates a clockwise rotation of the rotation input device112 or movement of the user's fingers around the rotation input device112 in a counterclockwise direction.

In addition, the controller 122 can determine other attributes of therotational input, such as speed or amount of rotation. For example, aspeed of rotation of the rotational input can be determined by detectinga duration of time that expires between the capacitance changes of eachchannel over the course of the rotation. The speed of the rotationalinput can indicate a slow rotation or a quick rotation. The controller122 can also detect an amount of rotation of the rotation input, such asa short rotation (e.g., quarter-turn, half-turn) or a long rotation(e.g., three-quarter turn, full-turn) of the rotation input device 112.Using various different combinations of detectable attributes of therotational input, such as the speed, direction, and/or amount ofrotation, enables the rotational input to have a variety of differentforms that can each be mapped to a unique operation or functionality ofa device connected to the cord 102.

At 608, a second example is illustrated in which the rotation inputdevice 112 includes six sensing wires 114. In at least some aspects, thesensing wires 114 are substantially equally spaced apart around thecenter portion 604 of the rotation input device 112. Here, the sensingwires 114 are arranged in a repeating configuration where the sensingpattern repeats over a 180-degree slice of the rotation input device112. This repeating mechanism has the advantage of providing a strongersignal for grips where the finger and thumb grip on opposite sides ofthe rotation input device 112, when compared to the simple three-wireconfiguration at 602. In one or more implementations, each of the sixsensing wires 114 can have a separate connection to the IC, which allowsfor symmetry to be implemented in software by adding the response ofopposing sensing wires together. Alternatively, each pair of opposingsensing wires 114 can have a same connection to the IC, which providesthe symmetry via hardware. For instance, opposing sensing wires 114-1and 114-2 both correspond to channel “1”.

At 608, the user grips the rotation input device 112 at locationscorresponding to the sensing wires 114 associated with channel “1”.Then, at 610, the user rolls the rotation input device 112 in acounterclockwise direction such that the touch input is now detected atchannel “2”. Rolling the rotation input device 112 further in thecounterclockwise direction results in the touch input being detected atchannel “3”. This pattern of capacitance changes over a duration of timevia channels “1”, “2”, and then “3” and so forth, indicates acounterclockwise rotation of the rotation input device 112. A pattern ofchanges in capacitance via channels “1”, “3”, and then “2” may indicatea clockwise rotation of the rotation input device 112.

In some aspects, the touch input may change the capacitance of multipleadjacent sensing wires 114. For instance, the user's thumb 402 may,either when gripping or rotating the rotation input device 112, touchadjacent sensing wires corresponding to channels “1” and “3”. When theuser rotates the rotation input device 112, as in 610, the thumb 402 maymove away from channel “3” and toward channel “2”, while stillactivating channel “1”. Here, a pattern is generated from channels “3”and “1” to channels “1” and “2”, which can be used to determine acounterclockwise rotation of the rotation input device 112.

The non-active part of the cord 102, such as the insensitive portion(106) may have a high impact on the sensitivity of the cord 102. Becausethe sensing wires 114 are twisted together inside a cable jacket, thereis a high capacitance between the wires. This high capacitance betweenwires can be offset, however, by introducing a shield wire, or by usinga sensing technique that cancels out the extra capacitance added by thewires inside the cord 102.

In a wire bundle, the closest metal objects to a sensing wire 114 areadjacent wires. Thus, a capacitive sense test on the sensing wire 114detects the capacitance of not only a user's finger, but also of thoseadjacent wires. Extra capacitance provided by the adjacent wires can beoffset or canceled out, however, by driving those wires at the samevoltage as the voltage used to sense capacitance on the sensing wire114, such as a square wave having a known amplitude and a knownfrequency. In this way, capacitance is measured when there is adifference in voltage between two sensing wires. If those two sensingwires have the same voltage, then there is no stored charge betweenthem.

The offset may be implemented by using the other sensing wires 114 inthe bundle. In aspects, each sensing wire 114 in the system is scannedindividually, one at a time, while the other sensing wires 114 remainidle. In one example, when sensing capacitance on a first sensing wirecorresponding to channel “1”, adjacent wires corresponding to channels“2” and “3” can be used to apply the voltage offset or the capacitivecancellation offset to the first sensing wire.

When using a shield wire, an offset signal is also used, but is drivenon another wire (or set of wires) that is wrapped around or otherwiseencompasses the sensing wires 114. In one or more implementations, theshield wire can be implemented as a separate braided shield thatsurrounds all the wires. Alternatively, the shield wire can beimplemented as a separate braided shield that surrounds each individualwire. In at least one example, a combination of shield wires can be usedto surround one or more individual wires and all the wires together. Theshield wire(s) shields the sensing wires from effects of parasiticcapacitance, which can include unwanted feedback resulting in parasiticoscillations of an amplifier circuit, stray inductance that resonateswith an inductor to make the inductor self-resonant, unwantedcapacitance that reduces bandwidth of an operational amplifier, orcrosstalk (e.g., signal from one circuit bleeding into another) betweencircuits resulting in interference and unreliable operation. In oneexample, the three sensing wires 114 at 602 can be twisted around eachother in the insensitive portions 106 of the cord 102, and then a shieldwire can be wrapped around all three sensing wires 114 to shield themfrom any extra capacitance from other wires in the bundle, such asheadphone wires or microphone wires.

Example Methods

FIG. 7 illustrates an example method 700 of detecting rotational inputvia a rotation input device on a capacitive sense cord. This method andother methods herein are shown as sets of blocks that specify operationsperformed but are not necessarily limited to the order or combinationsshown for performing the operations by the respective blocks. Thetechniques are not limited to performance by one entity or multipleentities operating on one device.

At 702, a plurality of capacitance values associated with sensing wiresof a capacitive sense cord are measured. For example, the controller 122(FIG. 1) measures one or more capacitance values associated with thesensing wires 114 of the cord 102. As described above, each sensing wire114 may be scanned individually, one at a time, to determine thecapacitance value of each sensing wire 114.

At 704, a pattern of change in a subset of the plurality of capacitancevalues over a duration of time is detected. For example, the controller122 detects a pattern of change in the capacitance values associatedwith sensing wires 114 of the cord 102. Example patterns of capacitancechanges are described in relation to FIG. 6.

At 706, it is determined whether the pattern of change in the subset ofcapacitance values corresponds to rotational input to a rotation inputdevice of the cord. For example, the controller 122 determines whetherthe pattern of change in the subset of capacitance values corresponds torotational input to the rotation input device 112 of the cord 102.Optionally, at 708, a direction of the rotational input is alsodetermined. For example, the controller 122 determines a direction ofthe rotational input (e.g., clockwise or counterclockwise) based on thepattern of change in the subset of capacitance values.

At 710, one or more functions are initiated based on the rotationalinput. For example, the controller 122 initiates one or more functionsthat are associated or otherwise mapped to the rotational input, such asincreasing or decreasing volume to a headset, scrolling through menuitems, and so forth. In some cases, the one or more functions areinitiated based at least in part on the direction of the rotationalinput, a speed of the rotational input, an amount of rotation of therotational input, and/or a sequence of different rotations.

Example Computing System

FIG. 8 illustrates various components of an example the computing system800 that can be implemented as any type of client, server, and/orcomputing device as described with reference to the previous FIGS. 1-7to implement a rotation input device on a capacitive sense cord. Inembodiments, the computing system 800 can be implemented as one or acombination of a wired and/or wireless wearable device, System-on-Chip(SoC), and/or as another type of device or portion thereof. Thecomputing system 800 may also be associated with a user (e.g., a person)and/or an entity that operates the device such that a device describeslogical devices that include users, software, firmware, and/or acombination of devices.

The computing system 800 includes communication devices 802 that enablewired and/or wireless communication of device data 804 (e.g., receiveddata, data that is being received, data scheduled for broadcast, datapackets of the data, etc.). The device data 804 or other device contentcan include configuration settings of the device, media content storedon the device, and/or information associated with a user of the device.Media content stored on the computing system 800 can include any type ofaudio, video, and/or image data. The computing system 800 includes oneor more data inputs 806 via which any type of data, media content,and/or inputs can be received, such as human utterances, touch datagenerated by the cord 102, user-selectable inputs (explicit orimplicit), audio and/or video signals transmitted via the cable 110,messages, music, television media content, recorded video content, andany other type of audio, video, and/or image data received from anycontent and/or data source.

The computing system 800 also includes communication interfaces 808,which can be implemented as any one or more of a serial and/or parallelinterface, a wireless interface, any type of network interface, a modem,and as any other type of communication interface. The communicationinterfaces 808 provide a connection and/or communication links betweenthe computing system 800 and a communication network by which otherelectronic, computing, and communication devices communicate data withthe computing system 800.

The computing system 800 includes one or more processors 810 (e.g., anyof microprocessors, controllers, and the like), which process variouscomputer-executable instructions to control the operation of thecomputing system 800 and to enable techniques for, or in which can beembodied, a capacitive sense cord. Alternatively or in addition, thecomputing system 800 can be implemented with any one or combination ofhardware, firmware, or fixed logic circuitry that is implemented inconnection with processing and control circuits which are generallyidentified at 812. Although not shown, the computing system 800 caninclude a system bus or data transfer system that couples the variouscomponents within the device. A system bus can include any one orcombination of different bus structures, such as a memory bus or memorycontroller, a peripheral bus, a universal serial bus, and/or a processoror local bus that utilizes any of a variety of bus architectures.

The computing system 800 also includes computer-readable media 814, suchas one or more memory devices that enable persistent and/ornon-transitory data storage (e.g., in contrast to mere signaltransmission), examples of which include random access memory (RAM),non-volatile memory (e.g., any one or more of a read-only memory (ROM),flash memory, EPROM, EEPROM, etc.), and a disk storage device. A diskstorage device may be implemented as any type of magnetic or opticalstorage device, such as a hard disk drive, a recordable and/orrewriteable compact disc (CD), any type of a digital versatile disc(DVD), and the like. The computing system 800 can also include a massstorage media device 816.

The computer-readable media 814 provides data storage mechanisms tostore the device data 804, as well as various device applications 818and any other types of information and/or data related to operationalaspects of the computing system 800. For example, an operating system820 can be maintained as a computer application with thecomputer-readable media 814 and executed on the processors 810. Thedevice applications 818 may include a device manager, such as any formof a control application, software application, signal-processing andcontrol module, code that is native to a particular device, a hardwareabstraction layer for a particular device, and so on.

The device applications 818 also include any system components, engines,or managers to implement a capacitive sense cord with a rotation inputdevice. In this example, the device applications 818 include thecontroller 122.

CONCLUSION

Although embodiments of a rotation input device for a capacitive sensecord have been described in language specific to features and/ormethods, it is to be understood that the subject of the appended claimsis not necessarily limited to the specific features or methodsdescribed. Rather, the specific features and methods are disclosed asexample implementations of a rotation input device for a capacitivesense cord.

What is claimed is:
 1. A capacitive sense cord comprising: a cable; acable jacket configured to cover the cable; and a plurality of sensingwires disposed inside the cable jacket and around the cable throughoutfirst and second portions of the cord, the first portion of the cordincluding the plurality of sensing wires disposed proximate to a surfaceof the cord and positioned lengthwise along the cord to form a rotationinput device configured to be capacitively sensitive to touch input, theplurality of sensing wires spaced apart from one another by virtue of amechanical object positioned within the rotation input device, themechanical object being locally thicker than the second portion of thecord, the rotation input device configured to enable rotational inputbased on a pattern of change in capacitance values corresponding to atleast a subset of the plurality of sensing wires in the rotation inputdevice; and the second portion of the cord configured to be relativelyless sensitive to touch input than the first portion of the cord.
 2. Thecapacitive sense cord of claim 1, further comprising a controllerconfigured to initiate, based on the rotational input, one or morefunctions at a computing device that is communicatively coupled to thecord.
 3. The capacitive sense cord of claim 2, wherein the controller isfurther configured to determine a clockwise or counterclockwisedirection of the rotational input based on the pattern of change in thecapacitance values.
 4. The capacitive sense cord of claim 1, furthercomprising a controller configured to initiate: a first function at acomputing device based on a first pattern of change in the capacitancevalues; and a second function at the computing device based on a secondpattern of change in the capacitance values that is different than thefirst pattern.
 5. The capacitive sense cord of claim 1, furthercomprising a shield wire wrapped around the plurality of sensing wiresin the second portion of the cord to shield the sensing wires fromeffects of parasitic capacitance.
 6. The capacitive sense cord of claim1, wherein the plurality of sensing wires are associated with at leastthree channels of an integrated circuit for detection of the pattern ofchange in capacitance values.
 7. The capacitive sense cord of claim 1,wherein the plurality of sensing wires are connected to an integratedcircuit via at least three channels, and wherein each of the at leastthree channels corresponds to two sensing wires of the plurality ofsensing wires that are disposed on opposing sides of the rotation inputdevice.
 8. A system comprising: a capacitive sense cord having aplurality of sensing wires disposed throughout a first portion of thecapacitive sense cord that is sensitive to touch input and a secondportion of the capacitive sense cord that is less-sensitive to touchinput than the first portion, the plurality of sensing wires beingdisposed proximate to a surface of the first portion of the capacitivesense cord and positioned lengthwise along the first portion of thecapacitive sense cord to form a rotation input device, the plurality ofsensing wires being spaced apart from one another in the first portionof the cord by virtue of a mechanical object that is positioned withinthe rotation input device and that is locally thicker than the secondportion of the cord; and a controller implemented at the capacitivesense cord, the controller configured to: measure capacitance valuesassociated with the plurality of sensing wires; detect a pattern ofchange in the capacitance values; determine that the pattern of changein the capacitance values corresponds to rotational input to therotation input device; and initiate one or more functions at a computingdevice communicatively coupled to the capacitive sense cord based on therotational input.
 9. The system of claim 8, wherein the controller isfurther configured to: determine a direction of the rotational input;and initiate the one or more functions based at least in part on thedirection of the rotational input.
 10. The system of claim 9, whereinthe determined direction of the rotational input corresponds to aclockwise or a counterclockwise direction around a center axis of therotation input device.
 11. The system of claim 8, wherein the pluralityof sensing wires are associated with at least three channels of anintegrated circuit.
 12. The system of claim 8, wherein the plurality ofsensing wires are connected to an integrated circuit via at least threechannels, and wherein each of the at least three channels is connectedto two sensing wires of the plurality of sensing wires that are disposedon opposing sides of the rotation input device.
 13. The system of claim8, wherein the capacitive sense cord includes a cable within the cablejacket, and wherein the cable is configured to communicate audio datafrom the computing device to a headset or transfer power or data to thecomputing device.
 14. The system of claim 8, wherein the controller isfurther configured to offset extra capacitance provided by adjacentsensing wires to a respective sensing wire of the plurality of sensingwires by driving the adjacent sensing wires and the respective sensingwire at a same voltage.
 15. The system of claim 8, wherein the pluralityof sensing wires are driven at a same voltage, and wherein thecontroller is configured to measure the capacitance values based on adifference in voltage between two or more of the plurality of sensingwires.
 16. The system of claim 8, wherein the capacitance sense cordincludes a shield wire configured to shield a respective sensing wire ofthe plurality of sensing wires from parasitic capacitance.
 17. Thesystem of claim 8, wherein the capacitance sense cord includes a shieldwire wrapped around the plurality of sensing wires in the second portionof the cord.
 18. The system of claim 8, wherein the cord comprises acord for ear buds or headphones, a data transfer cord, or a power cord.19. A method implemented by a controller coupled to a capacitive sensecord that includes a first portion that is sensitive to touch input anda second portion that is less-sensitive to touch input than the firstportion, the method comprising: measuring capacitance values associatedwith sensing wires of the cord that are disposed proximate to a surfaceof the first portion of the cord, positioned lengthwise along the firstportion of the cord to form a rotation input device, and spaced apartfrom one another in the first portion of the cord by virtue of amechanical object that is positioned within the rotation input deviceand that is locally thicker than the second portion of the cord;detecting a pattern of change in capacitance-sensing channels of anintegrated circuit that are coupled to the sensing wires; determiningthat the pattern of change in the capacitance-sensing channelscorresponds to rotational input to the first portion of the cord; andinitiating one or more functions based on the rotational input.
 20. Themethod of claim 19, further comprising determining a direction of therotational input based on the pattern of change in thecapacitance-sensing channels, wherein the initiating one or morefunctions is based at least in part on the direction of the rotationalinput.